public/platform/WebPrerenderingSupport.h

/*
 * Copyright (C) 2012 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef WebPrerenderingSupport_h
#define WebPrerenderingSupport_h

#include "WebCommon.h"

namespace blink {

class WebPrerender;

class WebPrerenderingSupport {
public:
    BLINK_PLATFORM_EXPORT static void initialize(WebPrerenderingSupport*);
    BLINK_PLATFORM_EXPORT static void shutdown();
    BLINK_PLATFORM_EXPORT static WebPrerenderingSupport* current();

    // A prerender link element is added when it is inserted into a document.
    virtual void add(const WebPrerender&) = 0;

    // A prerender is canceled when it is removed from a document.
    virtual void cancel(const WebPrerender&) = 0;

    // A prerender is abandoned when it's navigated away from or suspended in the page cache. This
    // is a weaker signal than cancel(), since the launcher hasn't indicated that the prerender isn't
    // wanted, and we may end up using it after, for instance, a short redirect chain.
    virtual void abandon(const WebPrerender&) = 0;

protected:
    WebPrerenderingSupport() { }
    virtual ~WebPrerenderingSupport() { }

private:
    static WebPrerenderingSupport* s_platform;
};

} // namespace blink

#endif // WebPrerenderingSupport_h